In animal models articular cartilage has been demonstrated to change in thickness and volume during extended periods of non-weight bearing. An accurate and reproducible magnetic resonance imaging method of non-invasively quantitating articular cartilage volumes has been developed and validated. We are using this method to follow the volume of the patellar articular cartilage in patients with recent ankle fractures who are non-weight bearing in that lower extremity. Cartilage volumes are measured on the day of the initial hospital visit and at intervals through their course of healing and recovery.